What does it mean when a guy says he feels protective over you?

A few months ago I was talking to this guy online it turned into a online relashionship we relized we lived about a hour a way from each other.. he started wanting to meet me and I never been in a relashionship before so I got nervous and backed off. today he messaged me for the first time in weeks he said he had a girl friend now and would like to be friends he also said he will always feel the need to be protective over me. what does that mean?